Straightening-die construction



Filed July 25, 1927 2 Sheets-Sheet Louie Borfliewiz. b, 3 WW his afforne Dec. 31, 1929. BORTKEWICZ STRAIGHTENINQ DIE CONSTRUCTION Filed July 25, 1927 2 Sheets-Sheet INVENTOR Louie Borf'kewicz by )3 97% his Mf'arneq FIG. 3

Patented Dec. 31, 1929 UNETED STATES PATENT OFFICE STRAIGHTENING-DIE CONSTRUCTION Application filed July 25,

This invention relates to an improvement in a die forging machine which is especially adapted to forge or reforge cutter bits for undercutting machines used in coal mines, and particularly relates to means for straightening cutter bits which have become bent. It has been found in practice, that cutter bits become bent and distorted in such a manner that they must be straightened be fore they can be reforged to obtain the desired pointing.

One object of the invention is to provide a machine in which a cutter bit, or similar article, is formed by a succession of relatively light blows, and in which a used cutter bit may be straightened prior to said forming operation.

Another object of the invention is to provide means to straighten cutter bits and the like, such means operating in conjunction with a forging machine of the type hereinafter described.

In the drawings Figure 1 is a plan view of the machine showing the cutter bit straightening device attached thereto; Figure 2 is a side elevation of the fore part of the ma chine; Figure 3 is a plan view of the straightening dies and their operating means; Figure 4 is a similar view showing the parts moved into the position which closes the straightening dies on a cutter bit; Figure 5 is a plan view showing a modified mounting of the straightening dies.

The machine comprises a bed 1 supported by a frame 2. As the applicants Patent No. 1,584,724, dated May 18, 1926, sets forth and describes the forging machine and its operation in detail, the description herein especially concerns the straightening dies and their operation. With reference to the cited patent, and to the drawings hereof, a slide bar 6 reciprocates in brackets 7 and 8, and car ries die 31 at one of its ends. The pair of ivotal side dies 33 which shape the sides of the cutter bit, are oscillated by two actuating arms 36. The bosses 44 on arms 36 contact the outward faces of the respective side dies 33 when the arms 36 move inwardly to engage and close the said side dies. The reciprocation of the slide bar 6 imparts angular 1927 Serial No. 208,076.

movement to the actuating arms 36. During the rearward movement of slide bar 6 the pivoted contact arms 43 come in contact with the hooked contact members 39 on the actuating arms 36. This movementforces the rearward ends of the actuating arms outwardly, the extent of their outward movement being increased by the tendency of the contact arms 43 to assume a position perpendicular to the slide bar. This oscillation of the actuating arms 36 causes their rearward portions to force the pivoted dies 33 inwardly against the stock. As the slide bar moves forwardly to bring the die 31 into contact with the stock, the leaf springs 45, which bear against the shanks of the dies 33, force the dies outwardly and force the actuating arms 36 back to the position shown in Fig. 1. This forging operation is clearly set forth in the above noted patent.

ivotally engaging the ends of actuating arms 36 are two links 3 and 4 which have die faces 5 and 5 respectively. The links 3 and 4 are mutually pivoted at 9, and as shown in Figures 1 and 3 are in their open position, so that the bent cutter bit 10 may be interposed between the die faces 5 and 5 In Figure 4 the moving parts are shown in the position which closes the die faces 5 and 5"* on the cutter bit 10 and straightens it. During the operation of the machine, the stock may be held in position between the straightening dies by means of tongs, or in an other suitable manner. The repeated blows of die faces 5 and 5 serve to straighten the bit. WVhen this straightening operation has been completed, the bit may be reheated and delivered to the feeding means of the main machine for the performance of a reforging operation.

Figure 5 shows a modified form of actuat ing arms 36. The important change in form is in having the extensions 4 made integral with the remainder of the arms 36*. Another new feature is in having the through bolts 11 replace the bosses 44. These bolts 11 may be screwed inwardly or outwardly to give the desired setting for their contact with side dies 33. In this modified form of straightening dies the bent cutter hit is placed between die faces 12 and, as the arms 36 oscillate, the bit is straightened. These die faces 12 are formed at a slight angle so that they lie parallel to each other for straighten- 5 ing the stock when the ends of the extensions 4' are caused to approach each other by oscillation of the arms 36 as a whole. The means for oscillating the actuating arms 86 are identical with those described with reference to Figures 3 and 4.

It is important to note that the essence of this invention is to add an additional function to the machine of the above noted patent and to other similar machines. With both forms of the arms for carrying the straightening dies, the dies are shown as die faces in tegral with the bodies of the arms. It should be understood, however that the dies may be made separately for attachment to the arms in any suitable manner.

What I claim is:

In a forging machine comprising two actuating arms pivoted part way of their length and including means operably adjacent the inner ends of said arms to oscillate the same together with pivotally interconnected cliecarrying arms pivotally mounted on the outer ends of said actuating arms, the pivotal interconnection of the die-carrying arms lying beyond the die faces carried thereby and lying beyond the points of pivotal connection of said die-carrying arms to said actuating arms.

In witness whereof, I hereunto set my hand.

LOUIE BORTKEWIOZ. 

